It seems that the app doesn't work with the Russian language. When I place a call I see the right name in Russian (it looks up in my Address Book), but when that side hangs up or alert ends, this name turns to strange non-readable symbols. I can see it in history list afterwards. Some names are that bad from the very beginning of the call (esp. when this is the name of the organization, no last or first name). Example: when I call "МИРЭА" I get "ÐÐÐ Ð­Ð"...

Maybe there is some way to change the default font? Looked through the app's main plist file and did't find such options...Any solutions for this?

This is tricky because Apple's Bluetooth HFP module manages the interface between the Mac and phone. I'll need to check if it has added any support for reporting or specifying the character encoding to be used. Phone Amego expects UTF8.